Magnetic clock

ABSTRACT

A magnetic clock comprises an inner revolvable magnetic member and an outer revolvable magnetic member, each being of generally hour glassed shaped and being arranged concentrically with respect to each other. An hour glassed shaped bearing is positioned concentrically between and exerts a repulsive force on the inner and outer members. The inner and outer revolvable magnetic members each have a plurality of circumferentially spaced apart peripheral elements integrally formed therewith which project radially outwardly therefrom. The outer revolvable member has a minute hand secured thereto for movement therewith and the inner revolvable member has an hour hand secured thereto for rotation therewith. An electro-magnet is positioned adjacent the periphery of the outer member and when energized causes the outer magnetic member to rotate through a predetermined arc of approximately 30*. An electrical pulse mechanism is connected to the electro-magnet and is operable to momentarily energize the electro-magnet which causes movement of the minute hand through the arc which corresponds to a 5 minute increment. The outer revolvable member is also provided with shiftable locking lugs which are shifted for engagement with the inner revolvable member when the outer revolvable member has revolved through an arc of 360*. With this arrangement, the inner revolvable member rotates with the outer member through an arc of 30* and this corresponds to the normal hour hand movement. Suitable magnetic holding means are provided for holding the inner and outer member against movement while the electro-magnet is in an unenergized condition.

I States Patent 1191 1 1 Dec. 4, 1973 1 MAGNETIC cLocK.

22' Filed: Jan. 12, 1973 21 App]; No.: 323,232

511 int. Cl. G04c 3/00, G04b 45/04 [58] Field of Search 58/2, 23 R, 23 o, I I 58/45 [56] References Cited UNITED STATES PATENTS 2,202,214 5/1940 Livingston et a1. 58/45 x I 3,451,280 6/1969 l-letz'el 58/23 R X 3,465,512 9/1969 Usui et al 58/45 X 3,541,778 11/1970 lngenito et al. 58/23 R 3,538,703 11 1970 -Walton et 41;. 58/23 R 3,675,055 7/1972 McShan 58/23 R x 3,712,046 1/1973 om 58/45 Primary Examiner-Richard B. Wilkinson- AiasTRAcT A magnetic clock comprises an inner revolvable magnetic member and an outer revolvable magnetic member, each being of generally hour glassed shaped and being arranged concentrically with respect to each v other. An hour glassed shaped bearing is positioned concentrically between and exerts a repulsive force on the inner and outer members. The inner and outer revolvable magnetic members each have a plurality of circumferentially spaced apart peripheral elements integrally formed therewith which project radially outwardly therefrom, The outer revolvable member has a minute hand secured thereto for movement therewith and the inner revolvable member has an hour hand secured thereto 'for rotation therewith. An electromagnet is positioned adjacent the periphery of the outer member and when energized causes the outer magnetic member to rotate through a predetermined arc of approximately 30. An electrical pulse mechanism is connected to the electro-magnet and is operable to momentarily energize the electro-magnet which causes movement of the minute hand through the arc which corresponds to a 5 minute increment. The outer revolvable member is also. provided with shiftable locking lugs which are shifted for engagement with the 1 inner revolvable member when the outer revolvable ymember has revolved through an arc of 360. With 3 Claims, 4 Drawing Figures t HMAIGNETICICLOCK BRIEF SUMMARY or THE INVENTION The object of this, invention is 'to provide a novel The 'revolvable'magnetic memberiwhich carries the minute hand is.revolvableIthr ogh QQarcof approximately 30 which movement corresponds to the movement of the minute hand on .a watch after the lapse of minutes. a

. An electro-ma'gnet positioned a ja n th p phs ry ofthe outerrevolvablemagnetic member carrying the minute hand is momentarily energized .byan electrical;

impulse produced by a pulse; generating. mechanism. The electro magnet is energizedatS. minute intervals and suitable holding magnets hold the magnetic mem- 1 her carrying the minute hand againstmovement during the period when'theelectro-magnet is' in a nonenergizedcondition.

*The revolvable magnetic member carrying the hour hand remains stationary until the-magnetic, member carryingthe minutehand has, been revolved through an arc of 360 which corresponds to .-t he.lapse of l .hour. When this occurs suitable locking lugsionthemagnetic 7 member carrying the minute hand are shifted into ena gagement with the other magnetic memberto rotate .the latter through the 30? arcso that it.points; to the next adjacent hour number;v Suitable holding magnets arealso provided and are effective for. holding the magnetic' member carrying the hour hand against movernentuntil the magnetic member carrying the .minute hand has been revolved through an arc of. 360.

- With this arrangement, an inexpensive highly effective clock is provided and the components thereof are subject to substantially no wear.

BRIEEDESCkIi TION OF THE DRAWINGS 1 is a front elevational view of the clock.

FIG. 2is a rear elevational view of the clock with the back cover removed.

' FIG. 3 is a cross sectional viewtakenapproximately along line 3-3 of FIG. 2 and looking in the direction of the arrows, and;

FIG. 4 is a diagrammatic view ofthe circuit of the clock.

DETAILED DESCRIPTION Referring now to the drawings it willbe seen that one embodiment of the novel clock, I designated generally by the reference numeral .10 is thereshownfThe clock includes a housing 11 which may beof any suitable design including a peripheral wall 12, a back. cover 13 v and a-front face-or-dial 114; A transparent frontcover' '15 covers and protects theface or dial l4 andaninner supporting wall 13a is positioned between the: front Referring nowto FIGS. 2 and} itwill be seen that the clock includes an outer magnetic memberl9 which is ofv e e a l hq rslas wn sura oni c ud n f or. upper frustro-conical portion 20 and a rear or lower frustro-conical portion The upper andlower. frnstro -conical portions join each other at awaist .22 it is pointed out that the outer magnetic member 19is ,of circular cross sectional configuration. I

, An inner ma ne m mb PQ$ fiQI 64 m wq trically within the outer magnetic meinber l9. inner magnetic member isalso ofhour glass configuration. The inner magnetic member includes a front or upper frustro-conical portion 524 and a rear or. lower frustro-conical portion 2 5; The upper and lower-frostro-conical portions join eachother at a waist 2 6. A cn a yhbu r a ha ta i n r -b ms i PP- sitioned concentrically between the inner'and outer magnetichrnembers .and the bearing also includes a 1 front or upper frustro-conical portion 28 and arear or lower; frustro conical portion 29. Thefrustro-conical portions of the bearing join each other at awaist Theinnerand outermagnetic members and the bearing are magnetized while rotatingat a high speed to eliminate crowning fields. When so magnetized, under controlled conditions, the polarity of the stationary 1 bearing is arrangedwith respectto the inner and outer a f he i a O t r m ne i emb s a the magnetic members so that each exert a repulsjive force i on each othenBecause of the hour glass configuration,

these. respectivemenibers are centered or stabilised both radially. and axially. It should bepointed outthat bea n ave he! u r n -fn r ica P qtion nne s r ts a d eih tsafi ass le Referring again to FIGS. 2 and 3', it will be seen-that the outer magnetic member 19 h as a plurality of circurnferentially spaced apart peripheral elements31 integrally formed with, the lower end 32 thereof and projecting radially outwardly therefrom lt willbe noted that in the. embodiments shown, the lower end actuy ne a l t a n s m, an the P phe a 9 I ements 31 are disposed in co-planar relationtherewith.

1 T nn m ne memb r s w w a p ura i y f p cumfet nti l s acs apa p riph e em n ich ar n eg m wi h w e 34 thereof which project outwardly therefrom. It

I will be noted that it isthe upper ends ofthe inner and outer magnetic members to which the minute and hour hands are affixed... Itwill further be noted that the peripheral elements 31 are positioned axially below the p riph e emen s 3 .A p f hq din a n s 35- a ovi ed-and a mounted by suitable brackets 36 .on1thehousing 11: of t c' oc It w be ted t t th heldi mag s 35 are disposed closely adjacent. the outerendof the pevripheral elements 33 of the inner magnetic member 23. Theholsfi s magn ep s t m d 9 t at the P larity-of the inwardly projecting end is opposite to the polarity of the outwardly projecting peripheral elements 4 u the e h ld m sne w ll en? o hQ the inner magnetic:v member. in apredetermined position until it is forcibly. evolved to a newposition.

face and back cover. The dial 1.4 has suitable hour indicia or numbers 16, arranged circumferentially there- 'around in a well known manner andthe dial is also provided with aminute hand 17 and a hourhandtl8 which are movable relative to the dial.

h ld n ma n 1 p i qns sl s y adjac the outer peripheral edge of theouter magnetic member 19 def ned by the peripheral elements 31 and it will be noted that the holding nagnet 37 is positioned to exertan atractiveforce with respect to the peripheral elements 31. An electro magnet38 is mounted in the I housing 11 and is disposed in opposed relation with rewith a pulse device 43.

Thepulse device 43is positioned within the housing 11 and in the embodiment shown the conductors 41 and42 are connected to a suitable source of electrical current such as the battery 44. An electrical conductor 45 isconnecte'd serially to the electrical conductor 41 and to one contact of a variable resistor or a potentiom- .eter' 47. The potentiometer 47 is connected serially to a time constant condensor 48. 1 An electricalconductor 46 is connected to the conductor 42 and is connected to one contact of a second variable resistor or potentiometer 49 which in turn is connected serially-to a field effect transistor 50. The condensor 48 is connected to'one contact of a double pole double throw switch 51, and another contact of the switch 51 vis-connected to the field effect transistor 50. The other contact of the switch 51 is connected to the potentiometer47. An electrical conductor 52 connects the field effect transistor to the electrical conductor- 46 through the winding of a relay 53. An electrical conductor 54 also connects the electrical conductor 46 to a field effect transistor. The relay ,53 includes a normally open switch 55 which is interposed in current controlling relation with respect to electrical conductor 42.- The relay 53 is also mechanically connected to switch 51,-t0 simultaneously Switch 55.

I During operation of the clock 10, the time constant operate switch 51 with condensor 48 will bealternately cycled through its leak down on discharging phase and its charging phase. After the'time has been charged, a negative charge will buildup at the contact 50a of the field effect transistor 50. As long asthe field effect transistor is subjected to a negative bias at contacts or gate 50a, then current will not flow from conductor 54 to conductor 52 and thereby close a potential across relay'winding 53. As the current (holding bias) leaks down from the time constant condensor 48 and from the gate 500 through the resistor 49, the negative bias at 50a progressively decreases until there is no negative bias at 50a and current will then flow from conductor 54 through the field effect transistor to conductor 52. This shuts the current across the relay field (conductors 52 and 54) and resistor 60. When this occurs,the relay switch circuit is closed and completes the pulse circuit to the battery 44 through conductor 41 to the trip coil 39. It is pointed out that switches 51 and 55 are closed when the relay circuit is energized.

When the trip coil 43 is energized, the peripheral element 31 of the outer magnetic member 19 which is positioned between the poles of the electro-magnet 38 will be shifted in a clockwise direction, as viewed in FIG. 3, because of the interaction of the magnetic forces of the electro-magnets and the outer magnetic member. In this respect,'it will be seen that the peripheral element 31 positioned between the poles of the electro-magnet will be urged in a clockwise direction by .the combined atractive and repulsive forces of the electro-magnet acting on the peripheral element. The

. 4 next adjacent peripheralelement will be urged in a clockwise direction and the repulsive force exertedby the pole of the electro-ma gnet closest adjacent the 'moving peripheral element will further urge the peripheral element in a clockwise direction. Since the trip coil is energized by an electrical impulse of momentary duration, the electro-magnet will be energized only for a time sufficient to shift the 'outer magnetic member through an arc so the next adjacent peripheral element is positioned between the poles of the electro-magnet.

As pointed out above, the switch 55 will be closed and the seitch 51 will be shifted to energize a trip coil 39 by a momentary impulse and the relay will then be de-energized. When the tripping circuit is deenergized, the switch 55 will be opened and the 'seitch 51 will be shifted to the postion illustrated in FIG. 4 to I gegin again the condensor discharging phase. The duration of the discharging phase is five minutes to that the pulse unit generates an electrical impulse to energize the coil 39 at 5 minute intervals. With this arrangement, the outer magnetic member is shifted relative to the face or dial of the clock at 5 minute intervals. The outer magnetic member with the minute hand attached thereto also revolves relation to the inner magnetic member until the outer magnetic member has revolved through an arc of 360.

I When the outer magnetic member 19 has revolved through an arc of 360, means are provided which will be actuated to interlock the outer magnetic member with the inner magnetic member so that the magnetic members will move together through the next increment of movement. To this end, the outer magnetic member 19 is provided with a pair of shiftable locking elements 56 formed of magnetic material and which are spaced apart a distance corresponding to a distance only slightly greater than the width dimension of oneof the peripheral elements on the inner magnetic member 23. These locking elements '56 are positioned adjacent and rearwardly of the peripheral element on the magnetic member which is disposed in the'sarne'vertical plane as the minute hand. 7

Thus when the minute hand ismoved to the number twelve on the dial which-also corresponds to the position of the electro-magnet as, the element 56 will shift vertically downwardly through a slot 57 in the supporting wall 13a when the electro-magnet is energized and will engage the peripheral element on the inner magnetic member 23. Thus when the outer magnetic member is then moved through its arc of 30 with minute hand on 12, the inner magnetic member will be revolved accordingly. The locking elements 56 will then be retracted since the electro-magnet 38 will be deenergized, the outer magnetic member will also have revolved to physically position the locking elements a sufficient distance away from force of the electro I From ,the foregoing description, it will be seen that I i have provided a novel magnetic clock which is not only of simple and inexepensive construction, but one which functions-in 'a more efficient manner than heretofore known comparable clocks.

What isclaimed is:

l. A clock comprising a first revolvable magnetic member of circular cross sectional configuration and having a plurality of circumferentially spaced apart peripheral elements integral therewith and projecting radially outwardly therefrom, 1

ban hour hand affixed to said first magnetic member and projecting radially therefrom,

a revolvable second magnetic member of circular cross-sectional configuration and positioned concentrically exteriorly of said first magnetic member, a plurality of circumferentially spaced apart peripheral elements integral with said second magnetic member and projecting radially therefrom, a minute hand connectedwith said second magnetic member and projecting radially therefrom,

a stationary magnetic bearing of circular crosssectional configuration and disposed concentrically between first and second magnetic members and exerting a repulsive force respectively on said first and second magnetic members, magnetic holding means positioned closely adjacent the peripheral elements on said first magnetic member, said holding means and said last mentioned peripheral elements exerting an attractive force on one another for normally holding the first "6 I magnetic member against movement, electro-magnetic means positionedclosely adjacent the peripheral elements on said second magnetic member and when energized causing said second magnetic member to revolve through a predetermined arc of approximately 30, electrical pulse means connected with said electromagnetic means and being operable to energize said electro-magnetic .means with a momentary electrical impulse whereby said second magnetic member will be moved through said predetermined are relative to said first magnetic member, and releasable locking means on said second magnetic member shiftable in response to movement of said second magnetic member through an arc of 360 relative to said first magnetic member, said locking means releasably engaging said first magnetic member to shift the same with said second revolvable member through said predetermined arc and then being shiftable out of engagement with said first magnetic member. v 2. The clock as defined in claim 1 and magnetic holding means positioned closely adjacent the peripheral elements on said second magnetic member, said last mentioned holding means and said last mentioned peripheral elements exertingvan attractive force on one another for normally "holding the second magnetic member against movement. I

3. The clock as definedin claim wherein said each of said magnetic members and said bearing are of hour glass configuration. 

1. A clock comprising a first revolvable magnetic member of circular cross sectional configuration and having a plurality of circumferentially spaced apart peripheral elements integral therewith and projecting radially outwardly therefrom, an hour hand affixed to said first magnetic member and projecting radially therefrom, a revolvable second magnetic member of circular cross-sectional configuration and positioned concentrically exteriorly of said first magnetic member, a plurality of circumferentially spaced apart peripheral elements integral with said second magnetic member and projecting radially therefrom, a minute hand connected with said second magnetic member and projecting radially therefrom, a stationary magnetic bearing of circular cross-sectional configuration and disposed concentrically between said first and second magnetic members and exerting a repulsive force respectively on said first and second magnetic members, magnetic holding means positioned closely adjacent the peripheral elements on said first magnetic member, said holding means and said last mentioned peripheral elements exerting an attractive force on one another for normally holding the first magnetic member against movement, electro-magnetic means positioned closely adjacent the peripheral elements on said second magnetic member and when energized causing said second magnetic member to revolve through a predetermined arc of approximately 30*, electrical pulse means connected with said electro-magnetic means and being operable to energize said electro-magnetic means with a momentary electrical impulse whereby said second magnetic member will be moved through said predetermined arc relative to said first magnetic member, and releasable locking means on said second magnetic member shiftable in response to movement of said second magnetic member through an arc of 360* relative to said first magnetic member, said locking means releasably engaging said first magnetic member to shift the same with said second revolvable member through said predetermined arc and then being shiftable out of engagement with said first magnetic member.
 2. The clock as defined in claim 1 and magnetic holding means positioned closely adjacent the peripheral elements on said second magnetic member, said last mentioned holding means and said last mentioned peripheral elements exerting an attractive force on one another for normally holding the second magnetic member against movement.
 3. The clock as defined in claim 1 wherein said each of said magnetic members and said bearing are of hour glass configuration. 